This is a continuation of an existing, productive, well-functioning, high volume Core with expert staff and state-of-the-art equipment essential for all five major projects and certain developmental projects outlined in this renewal application. Over the past four years the Core completed 825 work orders, developed 50 new immunohistochemical assays, prepared nearly 3500 paraffin blocks, processed 356 specimens into tissue arrays, performed 3500 immunohistochemical assays, and contributed to 32 published manuscripts. The objectives of the Pathology Core are to provide comprehensive histopathological support and pathology expertise to all SPORE projects. Services include tissue preparation, staining, laser capture microdissection, confocal microscopy, immunohistochemistry, and preparation of tissue arrays for both human and mouse specimens. Overall this Core will process 3590 human and animal tissue samples, and process and interpret 8935 slides for the proposed projects. This Core is essential to ensure quality and cost efficiency, and it has the necessary laboratory space, equipment, experienced histotechnologists, and expert pathologists to successfully manage this work.